阅读说明：本技术 一种可折叠式的固定梯 (Foldable fixed ladder ) 是由 陈佳纬 隆玉福 刘扬 刘长胜 赵浩翔 王帅 刘伟 张明 胡忠伟 李伟 肖顺贤 于 2019-09-29 设计创作，主要内容包括：本发明提供了一种可折叠式的固定梯,包括：固定梯主体,固定梯主体包括第一立柱、第二立柱、横杆、第一连接块和第二连接块；第一连接块固定在第一立柱上,第二连接块固定在第二立柱上,横杆的第一端与第一连接块可枢转地连接,横杆的第二端与第二连接块可枢转地连接；其中,第一连接块的下端具有第一避让部,第二连接块的上端具有第二避让部,以使固定梯具有使用时的打开状态,和收起的折叠状态。本发明的技术方案有效地解决了现有技术中固定梯在运输过程中占用空间大,运输不方便的问题。(The invention provides a foldable fixed ladder, comprising: the fixed ladder comprises a fixed ladder main body, a first connecting block and a second connecting block, wherein the fixed ladder main body comprises a first upright post, a second upright post, a cross rod; the first connecting block is fixed on the first upright post, the second connecting block is fixed on the second upright post, the first end of the cross rod is pivotally connected with the first connecting block, and the second end of the cross rod is pivotally connected with the second connecting block; wherein, the lower extreme of first connecting block has first portion of dodging, and the upper end of second connecting block has the second portion of dodging to make fixed ladder have the open mode when using, and the fold condition of packing up. The technical scheme of the invention effectively solves the problems of large occupied space and inconvenient transportation of the fixed ladder in the transportation process in the prior art.)

1. A collapsible fixed ladder, comprising:

the ladder comprises a fixed ladder main body (10), wherein the fixed ladder main body (10) comprises a first upright post (11), a second upright post (12), a cross bar (13), a first connecting block (14) and a second connecting block (15);

the first connecting block (14) is fixed on the first upright post (11), the second connecting block (15) is fixed on the second upright post (12), the first end of the cross rod (13) is pivotally connected with the first connecting block (14), and the second end of the cross rod (13) is pivotally connected with the second connecting block (15);

the lower end of the first connecting block (14) is provided with a first avoiding part, and the upper end of the second connecting block (15) is provided with a second avoiding part, so that the fixed ladder has an open state when in use and a folded state when in folding.

2. Foldable fixed ladder according to claim 1, characterized in that said first connection block (14) comprises a first mounting hole (141) through the upper and lower surfaces, said first upright (11) passing through said first mounting hole (141) and being fixed inside said first mounting hole (141).

3. Foldable fixed ladder according to claim 2, characterized in that said first connection block (14) comprises a first mounting notch (142), said first mounting notch (142) being a first groove from the bottom side upwards, said first groove running through the side away from said first upright (11).

4. Foldable fixed ladder according to claim 3, characterized in that said first connection block (14) further comprises a first pivot axle (143), said first end of said crossbar (13) has a first pivot hole adapted to said first pivot axle (143), said first pivot axle (143) is fixed on the side walls of both sides of said first recess.

5. Foldable fixed ladder according to claim 1, characterized in that said second connection block (15) comprises a second mounting hole (151) passing through the upper and lower surfaces, said second upright (12) passing through said second mounting hole (151) and being fixed inside said second mounting hole (151).

6. Foldable fixed ladder according to claim 5, characterized in that said second connection block (15) comprises a second mounting notch (152), said second mounting notch (152) being a second groove facing downwards from the upper surface, said second groove penetrating the side away from said second upright (12).

7. Foldable fixing ladder according to claim 6, characterized in that said second connection block (15) further comprises a second pivot axle (153), said second end of said crossbar (13) has a second pivot hole adapted to said second pivot axle (153), said second pivot axle (153) is fixed on the side walls of both sides of said second groove.

8. Foldable fixed ladder according to any of the claims 1 to 7, characterized in that said crossbars (13) are multiple, said first connection blocks (14) are multiple in one-to-one correspondence with said crossbars (13), said second connection blocks (15) are multiple in one-to-one correspondence with said crossbars (13).

9. Foldable fixed ladder according to any of the claims 1 to 7, characterized in that it further comprises conducting means (16), said conducting means (16) being connected to the upper end of the fixed ladder body (10).

10. Foldable fixed ladder according to claim 9, characterized in that said conducting means (16) comprises conducting rods, a ring with a gap and cross rods, the first ends of said conducting rods are connected to the fixed ladder body (10), the second ends of said conducting rods pass through the gap of said ring and are connected to the inner wall of said ring, said cross rods are located inside said ring and are connected to said conducting rods, and said cross rods, said conducting rods and said ring are in the same plane.

11. Foldable fixed ladder according to any of claims 1 to 7, characterized in that it further comprises grounding means (17), said grounding means (17) being connected to the lower end of the fixed ladder body (10).

12. Foldable fixed ladder according to claim 11, characterized in that said grounding means (17) comprises a wire (171) and a clamp (172), a first end of said wire (171) being connected to a lower end of said fixed ladder body (10) and a second end of said wire (171) being connected to said clamp (172).

13. Foldable fixing ladder as claimed in claim 12, characterized in that said clamp (172) comprises a clamp block (1721) and a fixing screw (1722), said clamp block (1721) is of U-shaped structure, one side wall of said clamp block (1721) has a screw hole, said fixing screw (1722) is movably connected with said clamp block (1721).

Technical Field

The invention relates to the technical field of auxiliary tools for overhead work, in particular to a foldable fixed ladder.

Background

The fixed ladder belongs to a type of ladder, and the ladder is done the limit by two long thick poles, and the middle horizontal pole that crosses suitable climbing for climb, ladder divide into single face ladder, lift single ladder and lift double ladder isotructure form. The fixed ladder is frequently used in daily life and also frequently used when the ground wire of the power transmission line is maintained.

At present, the structure of the fixed ladder in the prior art is basically consistent with that of a common ladder, and is usually realized by arranging a plurality of cross rods with fixed positions between two long rods.

However, the fixed ladder is mostly in an unfoldable structural form, so that the occupied space is large in the transportation process, and the transportation is inconvenient.

Disclosure of Invention

The invention mainly aims to provide a foldable fixed ladder, and aims to solve the problems that the fixed ladder in the prior art occupies a large space in the transportation process and is inconvenient to transport.

In order to achieve the above object, according to one aspect of the present invention, there is provided a foldable fixed ladder comprising: the fixed ladder comprises a fixed ladder main body, a first connecting block and a second connecting block, wherein the fixed ladder main body comprises a first upright post, a second upright post, a cross rod; the first connecting block is fixed on the first upright post, the second connecting block is fixed on the second upright post, the first end of the cross rod is pivotally connected with the first connecting block, and the second end of the cross rod is pivotally connected with the second connecting block; wherein, the lower extreme of first connecting block has first portion of dodging, and the upper end of second connecting block has the second portion of dodging to make fixed ladder have the open mode when using, and the fold condition of packing up.

Furthermore, the first connecting block comprises a first mounting hole penetrating through the upper surface and the lower surface, and the first stand column penetrates through the first mounting hole and is fixed in the first mounting hole.

Furthermore, first connecting block includes first installation breach, and first installation breach is by the ascending first recess of bottom surface, and first recess runs through the one side of keeping away from first stand.

Furthermore, the first connecting block further comprises a first pivot shaft, the first end of the cross rod is provided with a first pivot hole matched with the first pivot shaft, and the first pivot shaft is fixed on the side walls of the two sides of the first groove.

Furthermore, the second connecting block comprises a second mounting hole penetrating through the upper surface and the lower surface, and the second upright column penetrates through the second mounting hole and is fixed in the second mounting hole.

Further, the second connecting block comprises a second mounting notch, the second mounting notch is a second groove facing downwards from the upper surface, and the second groove penetrates through one side far away from the second upright post.

Furthermore, the second connecting block further comprises a second pivot shaft, the second end of the cross rod is provided with a second pivot hole matched with the second pivot shaft, and the second pivot shaft is fixed on the side walls of the two sides of the second groove.

Furthermore, the number of the cross rods is multiple, the number of the first connecting blocks is multiple in a one-to-one correspondence with the number of the cross rods, and the number of the second connecting blocks is multiple in a one-to-one correspondence with the number of the cross rods.

Furthermore, the fixed ladder also comprises a conducting device, and the conducting device is connected with the upper end of the fixed ladder main body.

Further, the conducting device comprises a conducting rod, a circular ring with a notch and a cross rod, the first end of the conducting rod is connected with the main body of the fixed ladder, the second end of the conducting rod penetrates through the notch of the circular ring to be connected with the inner wall of the circular ring, the cross rod is located in the circular ring and connected with the conducting rod, and the cross rod, the conducting rod and the circular ring are located in the same plane.

Further, the fixed ladder further comprises a grounding device, and the grounding device is connected with the lower end of the fixed ladder main body.

Further, the grounding device comprises a wire and a clamp, the first end of the wire is connected with the lower end of the fixed ladder main body, and the second end of the wire is connected with the clamp.

Further, anchor clamps include anchor clamps piece and set screw, and the anchor clamps piece is U type structure, and one side lateral wall of anchor clamps piece has the screw hole, and set screw is removable to be connected with the anchor clamps piece.

By applying the technical scheme of the invention, the first upright post, the second upright post, the cross rod, the first connecting block and the second connecting block of the fixed ladder main body are installed and matched for use, so that the folding and the unfolding of the fixed ladder main body are realized. The first connecting block is fixed on the first upright post, and the second connecting block is fixed on the second upright post, so that the installation is simple and the operation is convenient; but the both ends of horizontal pole are connected with first connecting block and second connecting block pivot ground respectively, the lower extreme of first connecting block is provided with the first portion of dodging, the upper end of second connecting block is provided with the second portion of dodging, when folding, the first end of horizontal pole can rotate downwards, the second end of horizontal pole can upwards rotate, when opening, the first end of horizontal pole can upwards rotate, the second end of horizontal pole downwards rotates, like this, realize folding and opening of fixed ladder, occupation space is less after the fixed ladder is folding, convenient transportation and deposit. The technical scheme of the invention effectively solves the problems of large occupied space and inconvenient transportation of the fixed ladder in the transportation process in the prior art.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 shows a schematic structural view of an embodiment of a folding fixed ladder according to the invention;

FIG. 2 is a schematic view showing the construction of a first connecting block and a second connecting block;

FIG. 3 shows a schematic structural view of an electrically conductive device;

fig. 4 shows a schematic structural view of the grounding device;

fig. 5 shows a partially enlarged schematic view at the earthing device a;

fig. 6 shows a schematic structural view of an open state of the folding fixed ladder;

fig. 7 shows a schematic structural view of the folded state of the fixed ladder body.

Wherein the figures include the following reference numerals:

10. a fixed ladder main body; 11. a first upright post; 12. a second upright post; 13. a cross bar; 14. a first connection block; 141. a first mounting hole; 142. a first mounting notch; 143. a first pivot shaft; 15. a second connecting block; 151. a second mounting hole; 152. a second mounting notch; 153. a second pivot shaft; 16. a conductive device; 17. a grounding device; 171. a wire; 172. a clamp; 1721. a clamp block; 1722. and fixing the screw.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Exemplary embodiments according to the present application will now be described in more detail with reference to the accompanying drawings. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. It is to be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art, in the drawings, the thicknesses of layers and regions are exaggerated for clarity, and the same devices are denoted by the same reference numerals, and thus the description thereof will be omitted.

As shown in fig. 1, the foldable fixed ladder of the present embodiment includes: the fixed ladder comprises a fixed ladder body 10, wherein the fixed ladder body 10 comprises a first upright post 11, a second upright post 12, a cross rod 13, a first connecting block 14 and a second connecting block 15. The first connecting block 14 is fixed on the first upright post 11, the second connecting block 15 is fixed on the second upright post 12, the first end of the cross rod 13 is pivotally connected with the first connecting block 14, and the second end of the cross rod 13 is pivotally connected with the second connecting block 15. Wherein, the lower end of the first connecting block 14 has a first avoiding part, and the upper end of the second connecting block 15 has a second avoiding part, so that the fixed ladder has an opening state when in use and a folding state when in folding.

By applying the technical scheme of the embodiment, the first upright post 11, the second upright post 12, the cross bar 13, the first connecting block 14 and the second connecting block 15 of the fixed ladder main body 10 are installed and matched for use, so that the fixed ladder is folded and unfolded. The first connecting block 14 is fixed on the first upright post 11, and the second connecting block 15 is fixed on the second upright post 12, so that the installation is simple and the operation is convenient; horizontal pole 13's both ends are connected with first connecting block 14 and second connecting block 15 pivot ground respectively, the lower extreme of first connecting block 14 is provided with the first portion of dodging, the upper end of second connecting block 15 is provided with the second portion of dodging, when folding, the first end of horizontal pole 13 can rotate downwards, the second end of horizontal pole 13 can upwards rotate, when opening, the first end of horizontal pole 13 can upwards rotate, the second end of horizontal pole 13 downwards rotates, and like this, realize folding and opening of fixed ladder, the folding back occupation space of fixed ladder is less, convenient transportation and deposit. The technical scheme of the invention effectively solves the problems of large occupied space and inconvenient transportation of the fixed ladder in the transportation process in the prior art.

As shown in fig. 1 and 2, in the solution of the present embodiment, the first connecting block 14 includes a first mounting hole 141 penetrating the upper and lower surfaces, and the first upright 11 passes through the first mounting hole 141 and is fixed in the first mounting hole 141. The first mounting hole 141 is adopted, so that the mounting operation of the first upright post 11 and the first connecting block 14 is simple. The fastening mode at the first mounting hole 141 is various, and may be: screw top tight, bayonet socket locking and interference fit.

As shown in fig. 1 and fig. 2, in the technical solution of the present embodiment, the first connecting block 14 includes a first installation notch 142, the first installation notch 142 is a first groove from the bottom surface to the top, and the first groove penetrates through a side away from the first upright 11. The first mounting notch 142 is in the form of a first groove, and the structure is simple to machine and can save cost.

As shown in fig. 1 and fig. 2, in the technical solution of the present embodiment, the first connecting block 14 further includes a first pivot shaft 143, the first end of the cross bar 13 has a first pivot hole adapted to the first pivot shaft 143, and the first pivot shaft 143 is fixed on the side walls at two sides of the first groove. The first pivot shaft 143 is inserted into the first pivot hole, the cross bar 13 can rotate around the first pivot shaft 143, specifically, the first pivot hole at the first end of the cross bar 13 is coaxially matched with the first pivot shaft 143, so that the first end of the cross bar 13 rotates around the first pivot shaft 143, and further the first end of the cross bar 13 is pivotally connected with the first connecting block 14, so as to complete the folding and opening actions of the fixed ladder. In addition, the arrangement of the first groove of the first connecting block 14 is used for installing the first pivot shaft 143, and preventing the first pivot hole of the cross rod 13 from falling off or sliding out from the first pivot shaft 143, and also plays a role in limiting the rotation angle of the cross rod 13 around the first pivot shaft 143, the rotation angle corresponds to the included angle between the folding state and the opening state of the cross rod 13, and the arrangement ensures stable structure, thereby ensuring safety in the using process.

As shown in fig. 1 and 2, in the solution of the present embodiment, the second connecting block 15 includes a second mounting hole 151 penetrating through the upper and lower surfaces, and the second upright 12 passes through the second mounting hole 151 and is fixed in the second mounting hole 151. The second mounting hole 151 is adopted, so that the mounting operation of the second upright post 12 and the second connecting block 15 is simple. The fastening mode of second mounting hole 151 department is various, can be: screw top tight, bayonet socket locking and interference fit.

As shown in fig. 1 and fig. 2, in the solution of this embodiment, the second connection block 15 includes a second installation notch 152, the second installation notch 152 is a second groove facing downward from the upper surface, and the second groove penetrates through a side away from the second upright 12. The second mounting notch 152 is formed as a second groove, which is easy to machine and can save cost.

As shown in fig. 1 and fig. 2, in the solution of this embodiment, the second connecting block 15 further includes a second pivot 153, the second end of the cross bar 13 has a second pivot hole adapted to the second pivot 153, and the second pivot 153 is fixed on the side walls of the second groove on both sides. The second pivot shaft 153 is arranged in the second pivot hole in a penetrating manner, the cross rod 13 can rotate around the second pivot shaft 153, specifically, the second pivot hole at the second end of the cross rod 13 is coaxially matched with the second pivot shaft 153, so that the second end of the cross rod 13 rotates around the second pivot shaft 153, and further the second end of the cross rod 13 is pivotally connected with the second connecting block 15, so that the folding and opening actions of the fixed ladder can be completed, and the second pivot shaft 153 and the second pivot hole are simple and reliable in structure and low in processing cost. In addition, the second groove of the second connecting block 15 is used for installing the second pivot shaft 153, and prevents the second pivot hole of the cross rod 13 from falling off or sliding out of the second pivot shaft 153, and also plays a role in limiting the rotation angle of the cross rod 13 around the second pivot shaft 153, the rotation angle corresponds to the included angle between the folding state and the opening state of the cross rod 13, and the arrangement ensures stable structure, thereby ensuring safety in the using process.

As shown in fig. 1, in the technical solution of the present embodiment, there are a plurality of cross bars 13, a plurality of first connecting blocks 14 are in one-to-one correspondence with the plurality of cross bars 13, and a plurality of second connecting blocks 15 are in one-to-one correspondence with the plurality of cross bars 13. The setting of a plurality of horizontal poles 13 makes the height that fixed ladder corresponds more nimble, specifically, can set up the quantity of horizontal pole 13 as required for fixed ladder has better practicality and universality.

As shown in fig. 6 and 7, in the solution of the present embodiment, the fixed ladder further comprises a conductive device 16 connected to the upper end of the fixed ladder body 10. The conductive device 16 is provided to facilitate connection of the fixed ladder main body 10 with other charged bodies, and to conduct charges from the charged bodies, thereby preventing workers from being shocked by electricity or equipment from being damaged by electric shock.

As shown in fig. 3, 6 and 7, in the technical solution of this embodiment, the conducting device 16 includes a conducting rod, a ring with a notch, and a cross rod, a first end of the conducting rod is connected to the fixed ladder main body 10, a second end of the conducting rod passes through the notch of the ring to be connected to an inner wall of the ring, the cross rod is located inside the ring and connected to the conducting rod, and the cross rod, the conducting rod and the ring are in the same plane.

The first end of conducting rod can be connected through modes such as screw-thread fit, bayonet connection, screw top are tight with the upper end of fixed ladder main part 10, and this kind of structure is easy to assemble and is dismantled. The structure of the conducting rod can be formed by mutually nesting a plurality of sections of conical tubes, wherein the conical tubes are hollow conical tubes with one end having a large diameter and the other end having a small diameter, when the conducting rod is stretched, the inner diameter of the conical tube at the lower position in the adjacent conical tubes is smaller than the outer diameter of the conical tube at the upper position, the inner diameter of the conical tube at the lower position far away from the matching position is larger than the inner diameter of the matching position, and the inner diameter of the conical tube at the upper position far away from the matching position is smaller than the inner diameter of the matching position; when the conductive device is contracted, the conical tube in the upper position can be sequentially contracted into the conical tube in the lower position, so that the conductive rod is stretched, the length of the conductive device 16 is adjusted, the conductive device is suitable for various distances, and the flexibility is higher.

In addition, the first upright post 11 and the second upright post 12 of the fixed ladder main body 10 can adopt a plurality of hollow cylindrical rods with different inner diameters, and are nested together one by one, and the hollow cylindrical rods are provided with a plurality of through holes which are perpendicular to the axial direction of the hollow cylindrical rods, are positioned at the middle positions and are on a straight line, after the positions of the hollow cylindrical rods are adjusted, the bolts penetrate through the through holes of two hollow cylindrical rods which are overlapped together, so that the position fixation of the adjacent hollow cylindrical rods is realized, further, the length adjustment and the fixation of the first upright post 11 and the second upright post 12 are realized, the telescopic function of the first upright post 11 and the second upright post 12 is realized, further, the length adjustment of the fixed ladder main body 10 is realized, the fixed ladder main body is suitable for various distances.

The cross rod connected with the second end of the conducting rod is used for binding a special fixed conducting wire, and the cross rod prevents the special fixed conducting wire from falling off, so that the safety is ensured; the second end of the conducting rod passes through the notch of the circular ring to be connected with the inner wall of the circular ring, the structure of the circular ring with the notch is arranged at the position, and the structure of the circular ring with the notch and the cross rod are arranged on the same plane, so that the special fixed conducting wire is prevented from falling off from the cross rod, on the other hand, the pointed structure of the cross rod cannot be damaged due to the arrangement of the circular ring, the use safety is ensured, and the conducting rod has strong attractiveness

As shown in fig. 6 and 7, in the solution of the present embodiment, the fixed ladder further includes a grounding device 17, and the grounding device 17 is connected to the lower end of the fixed ladder main body 10. The grounding device 17 is arranged to be fixed with a tower material of a tower on the ground, so that the stability of the fixed ladder during use is guaranteed, and the safety of workers is guaranteed due to the fact that a circuit is grounded.

As shown in fig. 4, 6 and 7, in the solution of the present embodiment, the grounding device 17 includes a wire 171 and a clamp 172, a first end of the wire 171 is connected to a lower end of the fixed ladder body 10, and a second end of the wire 171 is connected to the clamp 172. The first end of the wire 171 is connected to the lower end of the fixed ladder body 10, that is, to the lower ends of the first and second uprights 11 and 12, can be connected by means of bayonet, screw thread and the like, the connecting ends of the lead wire 171 and the first upright post 11 and the second upright post 12 can rotate 360 degrees, the clamp 172 is connected with the second end of the wire 171, the second end of the wire 171 is provided with a notch, a rotating pin is arranged in the notch, the clamp 172 comprises a clamp block 1721 and a connecting plate, the first end of the connecting plate is provided with a rotating hole matched with the rotating pin, the second end of the connecting plate is connected with the clamp block 1721 and rotates 180 degrees left and right along the rotating range of the rotating pin in the notch, the grounding device 17 has a structure of 360-degree rotation and 180-degree rotation, so that the clamp 172 can be suitable for being installed and fixed on tower materials at different positions and different angles, the flexibility is higher, and the safety factor is also improved.

As shown in fig. 4 and 5, in the solution of this embodiment, the clamp 172 includes a clamp block 1721 and a fixing screw 1722, the clamp block is U-shaped, a side wall of the clamp block 1721 has a screw hole, and the fixing screw 1722 is movably connected to the clamp block 1721. No special fixing clamp is arranged in the prior art, and the safety factor is not high. In the above technical solution, the clamp block 1721 is U-shaped, so that it is convenient to be fixed in cooperation with the tower material, and is easy and simple to operate and easy to use; screw hole that anchor clamps piece 1721's one side lateral wall set up, set screw 1722 is movably continuous with the anchor clamps piece, and this kind of structural design makes the tower material insert behind anchor clamps piece 1721's U type structure, through rotating set screw 1722, makes set screw 1722 top tightly insert the tower material of anchor clamps piece 1721's U type structure, reaches earthing device and the fixed purpose of tower material, guarantees safety to convenient to use, the fixed form is simple and reliable.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.